doc hdparm also support SATA
from the pg doc：
http://www.postgresql.org/docs/devel/static/wal-reliability.html :On Linux,
IDE drives can be queried using hdparm -I; write caching is enabled if
there is a * next to Write cache. hdparm -W 0 can be used to turn off write
caching. SCSI drives can be queried using
sdparm<http://sg.danny.cz/sg/sdparm.html>.
Use sdparm --get=WCE to check whether the write cache is enabled and sdparm
--clear=WCE to disable it.
from the hdparm man page :
http://linux.die.net/man/8/hdparm :hdparm - get/set SATA/IDE device
parameters
so,the doc is out date, it should mention hdparm also support SATA.
and this doc section current contains more IDE than SATA driver , but
nowadays, IDE driver is nearly dead, it hardly buy one IDE hard disk on the
market. so we should write more doc about SATA than IDE.
best regards,
--
Jov
blog: http:amutu.com/blog <http://amutu.com/blog>
On 04/07/2013 02:29 PM, Jov wrote:
from the pg doc：
http://www.postgresql.org/docs/devel/static/wal-reliability.html :On Linux,
IDE drives can be queried using hdparm -I; write caching is enabled if
there is a * next to Write cache. hdparm -W 0 can be used to turn off
write caching. SCSI drives can be queried using sdparm
<http://sg.danny.cz/sg/sdparm.html>. Use sdparm --get=WCE to check
whether the write cache is enabled and sdparm --clear=WCE to disable it.
The previous paragraph does say "Consumer-grade IDE and SATA drives are
particularly likely
to have write-back caches that will not survive a power failure."
I guess it's reasonable to replace "IDE" with "ATA/SATA" though it's
pretty minor. It'd be nice to confirm that the method for disabling the
write cache on fbsd is still correct and applies to SATA drives.
--
Craig Ringer http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services
On Sun, 2013-04-07 at 14:29 +0800, Jov wrote:
from the pg doc：
http://www.postgresql.org/docs/devel/static/wal-reliability.html :On Linux,
IDE drives can be queried using hdparm -I; write caching is enabled if
there is a * next to Write cache. hdparm -W 0 can be used to turn off write
caching. SCSI drives can be queried using
sdparm<http://sg.danny.cz/sg/sdparm.html>.
Use sdparm --get=WCE to check whether the write cache is enabled and sdparm
--clear=WCE to disable it.from the hdparm man page :
http://linux.die.net/man/8/hdparm :hdparm - get/set SATA/IDE device
parametersso,the doc is out date, it should mention hdparm also support SATA.
done
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